pathogens and host interactions

Pathogens are microorganisms like bacteria, viruses, fungi, or parasites that can cause diseases in other living organisms, known as hosts. When a pathogen enters a host, it can invade cells and reproduce, often triggering the host's immune response. This interaction can lead to illness, as the host's body fights back against the invader. The severity of disease depends on the pathogen's characteristics and the host's health and immune strength. Understanding these interactions helps in developing treatments and vaccines to prevent and manage infections effectively.